That thing follows start of football match (3)
I believe the answer is:
fit
'match' is the definition.
(fitting is a kind of matching)
'that thing follows start of football' is the wordplay.
'that thing' becomes 'it'.
'follows' says to put letters next to each other.
'start of' says to take the initial letters.
The first letter of 'football' is 'f'.
'it' after 'f' is 'FIT'.
(Other definitions for fit that I've seen before include "Healthy; spasm" , "'Sudden attack, of coughing say (3)'" , "Appropriate -- not 21" , "Sound in body or suitable" , "Appropriate kind of convulsion" .)